2015 Ambient Air Monitoring 

Network Plan 

Planning, Monitoring and Outreach Division 

May 2015 Public Review Draft 
2 

Table of Contents 

Introduction ........................................................................................................................................................ 4

General Information on Air Monitoring Networks ........................................................................................ 5

SLAMS Air Monitoring in San Luis Obispo County ......................................................................................... 7

Changes to Monitoring Network since the Previous ANP ......................................................................... 8

Opened, Closed, and Relocated Stations ................................................................................................ 8

Ozone Monitoring Network Changes .................................................................................................... 10

Particulate Monitoring Network Changes ............................................................................................. 10

Nitrogen Dioxide Monitoring Network Changes .................................................................................. 10

Sulfur Dioxide Monitoring Network Changes ....................................................................................... 10

Other Changes .......................................................................................................................................... 10

Detailed Network Descriptions ................................................................................................................... 11

Ozone Monitoring Network ..................................................................................................................... 11

Nitrogen Dioxide Monitoring Network .................................................................................................. 13

Sulfur Dioxide Monitoring Network ....................................................................................................... 13

Particulate Monitoring Network ............................................................................................................. 14

Other Networks......................................................................................................................................... 15

Proposed Network Changes and Improvements .....................................................................................16

New Stations and Station Closures and Relocations ........................................................................... 16

Ozone Monitoring Network ..................................................................................................................... 16

Nitrogen Dioxide Network ....................................................................................................................... 16

Sulfur Dioxide Monitoring Network ....................................................................................................... 16

Particulate Monitoring Network ............................................................................................................. 16

Other Changes and Improvements: ....................................................................................................... 16

Non-SLAMS Air Monitoring in San Luis Obispo County .............................................................................. 17

Oceano Dunes Monitoring .......................................................................................................................... 17

Price Canyon Monitoring ............................................................................................................................. 17

Air Quality Data................................................................................................................................................. 18

Appendix A: Minimum Monitoring Requirements ....................................................................................... 19

Minimum Monitoring Requirements for Ozone (O3) ............................................................................... 19

Minimum Monitoring Requirements for PM2.5 SLAMs............................................................................. 20
3 

Minimum Monitoring Requirements for Continuous PM2.5 Monitors ................................................... 20

Minimum Monitoring Requirements for PM10 ......................................................................................... 21

Minimum Monitoring Requirements for Nitrogen Dioxide (NO2) .......................................................... 21

Minimum Monitoring Requirements for Sulfur Dioxide (SO2) ............................................................... 22

Minimum Monitoring Requirements for Carbon Monoxide (CO) .......................................................... 22

Minimum Monitoring Requirements for Lead (Pb) at NCore ................................................................. 23

Source-Oriented Lead Monitoring (Including Airports) ........................................................................... 23

Appendix B: Collocation Requirements......................................................................................................... 24

Appendix C: Detailed Site Information .......................................................................................................... 25

Appendix D: EPA Approval Atascadero Site Move ....................................................................................... 46

Appendix E: Parallel Monitoring in Atascadero ............................................................................................ 49

Introduction ................................................................................................................................................... 49

Methods ......................................................................................................................................................... 49

Analysis .......................................................................................................................................................... 50

Timing of Parallel Monitoring .................................................................................................................. 50

PM2.5 Analysis ............................................................................................................................................ 52

Ozone Analysis .......................................................................................................................................... 54

Conclusion ..................................................................................................................................................... 54

Appendix F: Index to Items in Annual Monitoring Plan Checklist .............................................................. 57
4 

Introduction 

Every year the San Luis Obispo County Air Pollution Control District (SLOCAPCD) submits an ambient 

air monitoring network plan (ANP) to the United States Environmental Protection Agency (EPA); this 

document comprises the ANP for 2015. It is intended to fulfill federal requirements laid out in 40 

CFR 58.10 and to provide additional information about local monitoring activities to the public. 

Consistent with these goals and requirements, this ANP will be made available for public review for 

at least 30 days prior to its submission the EPA. All comments received and any SLOCAPCD 

responses to those comments will be submitted to EPA along with the ANP. 

The ANP is a snapshot of the air monitoring network as it currently exists and documents any 

changes since the last ANP (published May 2014) and any anticipated changes to the network over 

the next 18 months. This review and planning process helps ensure continued consistency with 

federal requirements and monitoring objectives. It also confirms and updates information in state 

and federal monitoring records. Information is provided for all ambient air pollution monitoring 

which occurred in the County, including sites operated by the California Air Resources Board (ARB). 

Data for ARB sites were obtained from that agency and are accurate to the best of our knowledge. 

As detailed in subsequent sections, the SLOCAPCD monitoring network remains unchanged since 

the last ANP with one exception: the relocation of the Atascadero station. Established at Atascadero 

Fire Station #1 in1988, it was moved in early 2015 to accommodate extensive renovations and new 

construction planned for the fire department property. The new location is less than a quarter of 

mile to the north of the original site, and all monitors were retained. A limited period of parallel 

monitoring of ozone and PM2.5 showed close agreement between the old and new locations. 

In 2015 we anticipate that two new source-oriented monitoring stations will commence operation. 

First, the SLOCAPCD has required the operator of the Price Canyon Oilfield to begin ambient 

monitoring for hydrogen sulfide at its oilfield, which is located between the cities of Pismo Beach 

and San Luis Obispo. Second, through local Rule 1001, we have required the California Department 

of Parks and Recreation to establish a PM10 monitor downwind of undisturbed, natural sand dunes 

within the Oceano Dunes State Vehicular Recreation Area (ODSVRA), a California State Park. The 

purpose of this monitor is to measure baseline, natural emissions. These measurements will be 

compared to PM10 levels measured at the CDF monitoring station, which is located downwind of the 

part of the ODSVRA where off-highway vehicle activity occurs. Both of these new sites will be 

operated by the permit holders (or their contractors), and SLOCAPCD will have real-time access to 

the data that is generated. 

 
5 

General Information on Air Monitoring Networks 

Most ambient air quality monitoring stations that are operated by air quality agencies are classified 

as State and Local Air Monitoring Station (SLAMS). SLAMS are long-term monitoring stations, and are 

generally considered to be permanent sites. Their primary objective is to collect data for comparison 

to the National Ambient Air Quality Standards (NAAQS). Stations may instead be classified as Special 

Purpose Monitors (SPM) or Prevention of Significant Deterioration (PSD) stations—these are 

generally short-term sites with objectives other than NAAQS comparison. 

Appendix D of 40 CFR 58 specifies design criteria for SLAMS networks and states that networks must 

be designed to meet a minimum of three basic monitoring objectives: 1. Provide air pollution data to 

the public in a timely manner; 2. Support compliance with the NAAQS; and 3. Support air pollution 

research. A variety of site types are needed to support these basic objectives, including the six 

general types identified in the Appendix: 

 Highest Concentration: Sites located to determine the highest concentration expected to 

occur in the area covered by the network; 

 Population Exposure: Those located to determine representative concentrations in areas of 

high population density; 

 Source Oriented: Sites located to determine the impact on ambient pollution levels of 

significant sources or source categories; 

 General/Background: Those located to determine general background concentration levels; 

 Regional Transport: Sites located to determine the extent of regional pollutant transport 

among populated areas, and in support of secondary standards; and 

 Welfare Related Impacts: Sites located to determine the welfare-related impacts in more 

rural and remote areas (such as visibility impairment and effects on vegetation). 

The physical siting of an air monitoring station must conform to the requirements of the Appendix, 

and its location must achieve a spatial scale of representativeness that is consistent with the 

monitoring objective and site type. The spatial scale results from the physical location of the site 

with respect to the pollutant sources and categories. It estimates the size of the area surrounding 

the monitoring site that experiences uniform pollutant concentrations. The categories of spatial 

scale defined in the Appendix are: 

 Microscale: An area of uniform pollutant concentrations ranging from several meters up to 

100 meters; 

 Middle Scale: uniform pollutant concentrations in an area of about 110 meters to 0.5 

kilometer; 

 Neighborhood Scale: an area with dimensions in the 0.5 to 4 kilometer range; 

 Urban Scale: Citywide pollutant conditions with dimensions from 4 to 50 kilometers; 

 Regional Scale: An entire rural area of the same general geography (this area ranges from 

tens to hundreds of kilometers); and 

 National and Global Scales.
6 

The relationship between site type and spatial scale is summarized in Table 1, below, which is 

adapted from Table D-1 of the Appendix. 

Table 1: Relationship between Site Type and Spatial Scale 

Site Type Appropriate Spatial Scale 

Highest Concentration Micro, middle, neighborhood, (sometimes urban 

or regional for secondary pollutants) 

Population Exposure Neighborhood, urban 

Source Oriented Micro, middle, neighborhood

General/Background Neighborhood, urban, regional

Regional Transport Urban, regional 

Welfare Related Impacts Urban, regional 
7 

SLAMS Air Monitoring in San Luis Obispo County 

San Luis Obispo County comprises the San Luis Obispo-Paso Robles Metropolitan Statistical Area 

(MSA). Air monitoring responsibilities for the MSA are divided between SLOCAPCD and ARB, as 

allowed by section 2(e) of Appendix D to 40 CFR 58. SLOCAPCD acknowledges this joint responsibility 

and is also a member of the ARB Primary Quality Assurance Organization (PQAO). The roles and 

responsibilities of the two agencies with regard to fulfilling State and Federal monitoring 

requirements are formalized in a “Roles and Responsibilities” document, which can be viewed on the 

ARB website.1

 

There are currently ten permanent ambient air monitoring stations (SLAMS) in the County/MSA; 

their locations are shown in Figure 1. Eight of these stations are operated by the SLOCAPCD as part 

of our network. ARB operates two additional stations in the county as part of their network, one in 

Paso Robles and the other in San Luis Obispo. Table 2 lists these stations, the pollutant and 

meteorological parameters that are monitored at each location and the site type. 

Table 2: Summary of Ambient Air Quality Parameters Monitored at SLAMS in San Luis Obispo County 

Site Ozoneb Nitrogen 

Dioxide 

Sulfur 

Dioxide PM10 PM2.5 Windc Temp 

Atascadero P, C P, C P P X X

Carrizo Plains T, B X X

CDF S, C S, C X 

Grover Beach X 

Mesa2 S, C S S X X

Morro Bay B B X 

Nipomo Regional Park (NRP) B B B X X

Paso Robles a P P X X

San Luis Obispo a P P P X X

Red Hills T, C X X

Site Types: B = General/Background, C = Highest Concentration, P = Population Exposure, T = 

Regional Transport, X = Parameter measured at this site, S = Source. 

Notes: a

 Paso Robles and San Luis Obispo are operated by ARB; all other sites are operated by 

SLOCAPCD. b

 Atascadero is the highest concentration site for the western county attainment area, 

while Red Hills is the highest concentration site for the eastern county non-attainment area. c

 Wind 

speed, wind direction, and sigma theta. 

 

1

 Air Resources Board, “Quality Management Documents, Document Repository, Finalized Roles and 

Responsibilities,” http://arb.ca.gov/aaqm/qa/pqao/repository/rr_docs.htm. 
8 

Changes to Monitoring Network since the Previous ANP 

Changes to the monitoring network since the publication of the last ANP in May of 2014 are 

summarized below. 

Opened, Closed, and Relocated Stations 

At the time of writing, no new stations have opened in the County, nor have any existing stations 

closed. 

As noted in the letter accompanying the submittal of our 2014 ANP, the host of our Atascadero 

SLAMS requested we move the station in order to accommodate planned renovations and new 

construction at the site (Atascadero Fire Station #1 at 6005 Lewis Avenue). Initially we thought that 

simply shifting the station several feet to the west would be adequate to accommodate their plans; 

however, after additional discussions it was decided that the station be completely removed from 

the property. Lift Station #5 at 5599 Traffic Way is identified as a potential new location for the 

station. It is within 400 m (one quarter mile) of the original site (Figure 2). EPA was consulted and 

approved the new location; a limited period of parallel ozone and PM2.5 monitoring suggested that 

any differences between these sites are negligible. See Appendix D for the EPA approval and 

Appendix E for a summary of the parallel monitoring. The station was relocated to this site in 

February 2015. All of the pollutants that were monitored at the original site (ozone, oxides of 

nitrogen, PM2.5, PM10 and meteorology), continue to be monitored at the new site. 

Figure 1: Locations of the 10 permanent SLAMS stations in San Luis Obispo County from May 2014 to 

May 2015. The thin red line depicts the boundary of the ozone non-attainment area.
9 

For each monitor, the objective, spatial scale, and site type are the same for the new site as they 

were for the old site. It should be noted that simply shutting the station down and discontinuing 

monitoring in the area is precluded, as this is the 2014 ozone design value site for the Western San 

Luis Obispo County ozone attainment area. (See Figure 1 for the boundary between the attainment 

and non-attainment areas of the county). Discontinuation of ozone monitoring is also precluded by 

40 CFR 58.14(c)(1), since the upper 90% confidence bound of mean of the last five years of design 

values (0.0642 ppm) is greater than 80% of the ozone NAAQS (0.060 ppm).2

 Finally, with a 25-year 

history of air monitoring, the site is highly valuable for tracking long-term air quality trends, and it is 

therefore highly desirable to continue monitoring at an equivalent site in the area. 

 

2

 The 2010 through 2014 ozone design values are 0.065, 0.062, 0.063, 0.062, 0.063 ppm. Their mean 

and standard deviation are 0.0630 and 0.0012 ppm, respectively, and therefore the 90% confidence 

interval of the 5-year mean is 0.0618 to 0.0642 ppm. 

Figure 2: Locations of the original and new Atascadero ambient air monitoring sites.
10 

Ozone Monitoring Network Changes 

Other than the aforementioned relocation of the ozone monitor in Atascadero, there has been only 

one change to the network: the monitor at Red Hills was upgraded from a Teledyne-API 400A to a 

T400 in March 2015. 

Particulate Monitoring Network Changes 

Other than the relocation of the PM10 and PM2.5 monitors in Atascadero, there have been no changes 

to the particulate monitoring network. 

Nitrogen Dioxide Monitoring Network Changes 

In addition to the relocation of the Atascadero NO2 monitor, the Teledyne-API 200A instrument at 

this station was upgraded to a T200 instrument in November 2014. 

Sulfur Dioxide Monitoring Network Changes 

No changes were made to the sulfur dioxide monitoring network. 

Other Changes 

 The data loggers at the following sites were upgraded from ESC 8816s to ESC 8832s: 

Atascadero (June 2014), CDF (July 2014), Mesa2 (July 2014), and NRP (July 2014). 

 The zero-air generator at Mesa2 was upgraded from a Teledyne-API 701 to a T701H in May 

2014. The zero-air generator is a component of the gas calibration system at this site. 

 A wall mounted air conditioning unit was installed at CDF in May 2014. 

 In April 2014 the naturally aspirated temperature sensor at Carrizo Plains was replaced with 

a fan aspirated system (Met One Instruments 060A-2 probe and 076B radiation shield) and 

moved from a height of 3 meters to 7 meters. (This should have been mentioned in the last 

ANP but was inadvertently omitted.) 

 In February 2015 the Climatronics temperature sensor at Atascadero failed and was 

replaced with a Met One Instruments system (060A-2 probe and 076B radiation shield). 
11 

Detailed Network Descriptions 

Ozone Monitoring Network 

All SLAMS in the county monitor for ozone except for CDF, Mesa2, and Grover Beach (see Table 2). 

The SLAMS network in San Luis Obispo County thus features ozone monitors located in Atascadero, 

Red Hills, Carrizo Plains, Paso Robles, Morro Bay, San Luis Obispo, and Nipomo Regional Park. 

Atascadero – SLOCAPCD has operated an ozone monitor in Atascadero since 1988. As noted above, 

this station was moved in 2015 from a site located in the central business district of downtown 

Atascadero to a nearby city property. The original location was bounded on two sides by public 

schools, and the new site is adjacent to a community center. The monitor continues to be classified 

as population-oriented and neighborhood scale. It also records the highest ozone concentrations in 

the western San Luis Obispo attainment area. It provides a measurement of representative ozone 

concentration for the City of Atascadero. Ozone concentrations at this site exhibit strong diurnal 

fluctuations caused by the titration of ozone with oxides of nitrogen from nearby mobile and 

residential sources. Measured concentrations at this site are similar to those recorded at Paso 

Robles, and are often the highest among the five ozone monitors in the western portion of the 

County that is classified as attaining the federal ozone standard. The highest ozone concentrations 

at Atascadero occur when high pressure over the interior southwest U.S. causes transport of ozone 

and other pollutants into the county from the east. Under these infrequent conditions, transported 

ozone enhanced by local pollutants can cause highly elevated concentrations. The prevailing winds 

from the west and northwest help keep ozone levels at Atascadero low most of the time. 

Carrizo Plains – Operated by SLOCAPCD since January 2006, this station monitors background 

levels and ozone transport from the interior areas of the state on a regional scale. The monitor is 

located in an outbuilding at the Carrizo Plains Elementary School. The ozone concentrations 

recorded here are second only to Red Hills in concentration and persistence; it is also located within 

the Eastern San Luis Obispo County non-attainment area. 

Morro Bay – Operated since 1975 by SLOCAPCD, this site provides regional scale and 

general/background ozone monitoring. Located in downtown Morro Bay, the monitor generally 

measures background levels of ozone from the predominant northwest winds blowing off of the 

Pacific Ocean. Under unusual meteorological conditions, the site can record elevated ozone 

concentrations transported from urban areas as far south as the Los Angeles basin. 

Nipomo Regional Park – Operated by SLOCAPCD since 1998, this station provides monitoring of 

background levels of ozone on a regional scale. Previously (1979 to 1996) ozone had been 

monitored in Nipomo on Wilson Street several miles away. The ozone concentrations measured at 

NRP are representative of interior portions of the Nipomo Mesa and are the highest recorded in the 

coastal region of San Luis Obispo County. 

Paso Robles – Operated by ARB since 1974, this population-oriented neighborhood scale ozone 

monitor provides a representative ozone concentration for the suburban areas of the City of Paso 
12 

Robles. The conditions under which elevated ozone levels occur and the location’s prevailing winds 

are similar to Atascadero. 

Red Hills – Operated by SLOCAPCD since 2000, this station is located on the summit of the Red Hills 

at an elevation of about 2,000 feet. It is in a very sparsely populated area, near the community of 

Shandon. This regional scale site is often influenced by ozone transport from distant pollutant 

source areas outside of the County, and it consistently records the highest and most persistent 

ozone concentrations in the network; its site type is thus regional and maximum concentration. In 

early 2012, the eastern portion of the County was designated as marginally non-attainment for the 

federal 8-hr ozone standard based on the design value from this site. 

San Luis Obispo – ARB has operated a population-oriented, neighborhood scale ozone monitor in 

the City of San Luis Obispo since 1970. The monitor has been at its current site since 2005. It 

provides a representative ozone concentration for the City of San Luis Obispo. The monitor is 

located in the urban area where ozone concentrations are significantly depleted by titration with 

local mobile and stationary NOx sources. As a result the concentrations recorded here are often 

lower than at Morro Bay. 

As noted in Table 2, the SLAMS site types employed by the existing ozone network are: 

1. Highest Concentration – The Red Hills station typically records the highest ozone 

concentrations in the County. The high ozone levels tend to occur in the interior areas of the 

County during summer, either following long periods of wind stagnation, or as a result of 

offshore winds which can transport pollutants from interior regions of the state from distant 

sources to the northeast. Among the sites in the western portion of the County, which are 

classified as attaining the ozone standard, Atascadero and Paso Robles measure the highest 

concentration. In 2014, Atascadero had a higher design value than Paso Robles, but in 

previous years Paso Robles has often been higher. 

2. Population Exposure – The Paso Robles, Atascadero, and San Luis Obispo monitors provide 

a good representation of the ozone levels in the larger cities of the County. 

3. Source Impact – Because ozone is a secondary pollutant, the effect of emissions from any 

single source are experienced five to seven hours later and often many miles distant. As a 

regional pollutant, monitoring for specific sources of ozone is not performed. 

4. General/Background – The monitors at Morro Bay, Carrizo Plains and Nipomo Regional 

Park provide regional background ozone levels. 

5. Regional Transport – The stations located at Carrizo Plains and Red Hills provide excellent 

surveillance of regional transport of ozone in the interior part of the county. Coastal 

monitoring stations have provided evidence in the past of regional transport of ozone over 

the Pacific Ocean from distant urban sources. 
13 

Nitrogen Dioxide Monitoring Network 

The SLAMS network in San Luis Obispo County features nitrogen dioxide (NO2) monitors at 

Atascadero, Morro Bay, and Nipomo Regional Park. NO2 levels have always been well below the 

state and federal standards at all locations in our County. For this reason NO2 monitoring is most 

useful here as an indicator of depletion of ambient ozone through titration with nitric oxide. Having 

at least one NO2 monitor in each geographical region of the County also serves a long-term air 

quality surveillance role. 

Atascadero – Operated by SLOCAPCD since 1990 and relocated in 2015, this population-oriented 

monitor is considered neighborhood scale. This is the only NO2 monitor in the Salinas River air 

basin, and it records the highest NO, NO2 and NOx levels in the County. The monitor’s downtown 

location has established a strong diurnal inverse relationship between ozone and NO2 levels caused 

by local mobile sources and residential and commercial combustion of natural gas. 

Morro Bay – Operated by SLOCAPCD since 2001 this monitor is neighborhood scale and was 

established to monitor emissions from the Morro Bay power plant, located less than a mile upwind. 

The plant permanently closed in February 2014. 

Nipomo Regional Park – Operated by the SLOCAPCD since 1998, this monitor is regional in scale 

and is representative of background concentrations on the Nipomo Mesa. The site’s location in a 

large natural area away from local or mobile sources makes it ideal for regional surveillance of NO2. 

The SLAMS sites in the existing NO2 network are: 

1. Highest Concentration – The Atascadero monitor historically has measured the highest 

NO2 concentrations in the county. NO2 levels are the result of titration of ambient ozone by 

local sources of nitric oxide and as a result values are always relatively low. Levels have 

never exceeded the 1-hr NO2 standard (100 ppb), with annual maximum 1-hr concentrations 

typically around 50% of the standard. 

2. General/Background – With no significant local sources present, the monitors at Nipomo 

Regional Park and Morro Bay provide excellent information on coastal background levels of 

NO2. 

Regional Transport and Welfare-Related impacts of NO2 are not currently addressed by the District’s 

SLAMS network and are not thought to be significant. With the closure of the Morro Bay power plant 

in 2014—the only potentially significant point source of NO2 in the County—no monitors in the 

network are considered to be source-oriented. The San Luis Obispo-Paso Robles MSA, does not 

have—nor per Appendix D, Section 4.3 of 40 CFR 58 is it required to have—any NO2 sites for 

vulnerable populations, near-road NO2 monitoring sites, or area-wide NO2 sites. 

Sulfur Dioxide Monitoring Network 

The sulfur dioxide (SO2) monitoring network in San Luis Obispo County currently consists of one 

station: Mesa2. 
14 

Mesa2 – Established in 1989 and operated by the SLOCAPCD since 2006, this monitor performs 

surveillance of a nearby oil refinery. It is considered middle scale and highest concentration for SO2. 

Since it is located close to and downwind of a major source of SO2 emissions, it is representative 

only of the immediate area. The station was sited to optimize surveillance of the refinery’s nearby 

coke calciner, which has since been shut down. Nonetheless, the refinery remains the largest point 

source of SO2 in the County, and during upsets this monitor can record concentrations approaching 

and sometimes exceeding the NAAQS. In addition to meeting NAAQS compliance objectives, this site 

is also vital for public information and emergency response. 

The SLAMS SO2 monitoring objectives met by the network are: 

1. Highest Concentration – The monitor at Mesa2 currently records the highest SO2 levels in 

the County. 

2. Source Impact – The monitor at Mesa2 is invaluable in determining the SO2 source impact 

upon the immediate region. 

Monitoring objectives not addressed by the existing SO2 network are: General/Background, 

Population, Regional Transport, and Welfare-Related. Historical SO2 monitoring performed 

elsewhere in the county (at NRP from 1998-2006; Morro Bay, 1979-1995; Grover Beach, 1982-2004; 

and at decommissioned stations in Arroyo Grande “Ralcoa” (06-079-1005), 1991-2002, and “Mesa1” 

(06-079-3002), 1987-94) has provided good evidence that monitoring for these objectives is not 

needed. Furthermore, background levels of SO2 in the County are believed to negligible, since more 

than 98% of hourly SO2 levels from Mesa2 were 1 ppb or less in 2014. 

Particulate Monitoring Network 

The particulate monitoring network in San Luis Obispo County consists of six Federal Equivalent 

Method (FEM) PM10 monitors (Paso Robles, Atascadero, San Luis Obispo, Mesa2, CDF and Nipomo 

Regional Park) and four FEM PM2.5 monitors (Atascadero, CDF, Mesa2 and San Luis Obispo). The PM10

network has been in place since 1988, and PM2.5 samplers began operation in 1999 in response to 

the establishment of a new federal standard for PM2.5 in 1997. Originally all particulate monitoring in 

the County was performed as part of ARB’s network, but eventually all monitors except those at 

Paso Robles and San Luis Obispo became part of the SLOCAPCD network. Note that for quality 

assurance the District remains part of the ARB PQAO. SLOCAPCD therefore relies on ARB to perform 

federally required audits of its particulate monitors and to meet federal collocation requirements. 

Initially, all particulate sampling was conducted by filter-based Federal Reference Method (FRM) 

methods. With the advent of continuous monitoring technologies, all the FRM monitors in the 

County have been replaced with FEM monitors in recent years. These are continuous semi-real time 

monitors that report hourly PM concentrations. The hourly data has greatly improved the 

SLOCAPCD abilities to issue timely air quality forecast which is a significant benefit for the 

advancement of public health goals. 
15 

Atascadero – Operated by SLOCAPCD, PM10 monitoring has been conducted here since 1988, 

initially via a FRM and currently with a continuous FEM monitor. Collocated FRM PM2.5 monitors 

began operation in 1999 and have since been replaced by a single FEM. All monitors are 

neighborhood in scale and representative of particulate concentrations in the City of Atascadero. As 

previously noted, the station was moved about 400m north of its original location in February 2015. 

CDF – Originally established for the SLOCAPCD’s Nipomo Mesa Phase 2 Particulate Study, this site 

has become a permanent part of SLAMS particulate network. The site features continuous FEM 

samplers for PM10 and PM2.5, which are neighborhood in scale and measure source impacts from 

the ODSVRA. These monitors record the highest particulate levels in the County and are strongly 

influenced by the ODSVRA, located directly upwind. In 2012, extensive temporary monitoring on the 

Nipomo Mesa confirmed that this site is located within the 1 square mile sector of the study area 

that experiences the highest PM10 levels.3

 

Mesa2 – PM10 sampling began at this site in 1991, and the monitors have been operated by the 

SLOCAPCD since 2006. This site initially featured collocated FRM PM10 samplers that were replaced 

by a single continuous FEM PM10 monitor in 2009. A continuous PM2.5 FEM monitor was installed at 

the same time. This site monitors source impacts from the nearby oil refinery and coastal dunes and 

the monitors are considered to be neighborhood scale. These monitors record some of the highest 

particulate levels in the County and are strongly influenced by the extensive coastal sand dunes and 

the ODSVRA located upwind. 

Nipomo Regional Park – Operated at this location by SLOCAPCD since 1998, it replaced a site at 

Wilson Street in Nipomo that operated from 1990-96. The 1-in-6 day FRM PM10 sampler was 

replaced with a continuous FEM sampler in 2010. The monitor is regional in scale and is 

representative of PM10 concentrations on the Nipomo Mesa. 

Paso Robles – Operated by ARB since 1991 this PM10 monitor is urban in scale and representative of 

the city of Paso Robles. The FRM sampler at this site was replaced with an FEM PM10 sampler in 

August 2009. 

San Luis Obispo – Operated by ARB, a PM10 sampler has been in place since 1988, and a PM2.5 

sampler since 1999. ARB replaced the FRM samplers with continuous FEM instruments in 2011. 

These population-oriented monitors are neighborhood in scale and represent particulate 

concentrations in the City of San Luis Obispo. 

Other Networks 

San Luis Obispo County, which comprises the San Luis Obispo-Paso Robles MSA, is not required to 

have—nor does it have—any NCORE, PAMS, lead, carbon monoxide or near-road monitoring 

stations. 

 

3

 San Luis Obispo County Air Pollution Control District, “South County Community Monitoring 

Project,” January 2013. Available online: http://slocleanair.org/communitymonitoringproject 
16 

Proposed Network Changes and Improvements 

The following modifications will likely occur in the 18 month period after the publication of this ANP. 

New Stations and Station Closures and Relocations 

Currently, there are no plans to establish any new SLAMS or to close or relocate any existing stations 

within the next 18 months. Note that with a population well below 500,000, the San Luis ObispoPaso Robles MSA/CBSA4

 is not required to have any near-road NO2, CO, or PM2.5 monitors, and 

therefore SLOCAPCD has no plans to establish any such monitors. 

Ozone Monitoring Network 

The ozone monitor Carrizo Plains is scheduled to be upgraded from a Teledyne-API 400A instrument 

to a T400. 

Nitrogen Dioxide Network 

No changes to the nitrogen dioxide monitoring network are anticipated. 

Sulfur Dioxide Monitoring Network 

No changes to the sulfur dioxide monitoring network are anticipated. 

Particulate Monitoring Network 

No changes to the particulate monitoring network are anticipated. 

Statement Regarding Review of Changes to the PM2.5 Network 

In the event that SLOCACPD needs to change the location of a PM2.5 monitor that records violations 

of the NAAQS, the agency will notify EPA Region 9 and ARB contact points immediately, and work 

closely with ARB to formulate a plan for moving the site. The public will be notified of the plan and 

provided with an opportunity to comment for at least 30 days. Finally, the agency will submit formal 

notification to EPA. The SLOCAPCD intends to discuss and receive approval of any changes to our 

PM2.5 Network—whether they affect monitors violating NAAQS or not—with ARB and EPA prior to 

making them, however unforeseen circumstances (e.g. unexpected loss of site access) may preclude 

this. 

Other Changes and Improvements: 

1. The ozone calibrator at Red Hills is scheduled to be upgraded from a Teledyne 703E to a 

T703. Pending funding, other calibrators may also be upgraded from E to T-series 

instruments. 

2. All sites are scheduled to have high speed internet connections installed, and data retrieval 

will be upgraded from dial-up communication at 9600 baud to retrieval over the internet. 

 

4

 San Luis Obispo County, the San Luis Obispo-Paso Robles MSA, and the San Luis Obispo-Paso 

Robles Core Based Statistical Area (CBSA) have identical borders and populations. 
17 

Non-SLAMS Air Monitoring in San Luis Obispo County 

Oceano Dunes Monitoring 

Frequent exceedences of the California Ambient Air Quality Standard for 24-hour PM10 (50 g/m3) 

are observed downwind of the ODSVRA on the Nipomo Mesa. To address these exceedences, the 

SLOCAPCD Board of Directors approved Coastal Dunes Dust Control Rule 1001. The rule requires, 

inter alia, the ODSVRA operator (i.e., California State Parks) to monitor PM10 levels in at least two 

locations within or downwind of the ODSVRA: one downwind of an area where off-road vehicle 

activity is allowed (“riding area monitor”), and another downwind of a comparable area where offroad vehicle activity is not allowed (“control site monitor”). This monitoring is to be performed with 

continuous FEM monitors.5

SLOCAPCD and the operator have agreed to use our CDF monitoring station as the riding area 

monitor. This site will continue to be operated by SLOCAPCD as a SLAMS. The operator is in the 

process of establishing the control site monitor within the ODSVRA. This site will host a MetOne BAM 

1020 as its PM10 monitor and will also have meteorological equipment. Rule 1001 requires the PM10

monitor to be operational and reporting data by May 31, 2015. It will be operated by SLOCAPCD, and 

raw data will be available in real-time. Validated data will be reviewed by the District, and we will 

upload the data to the Air Quality System (AQS). This site will be designated as special purpose 

monitor in AQS rather than as a SLAMS. 

Also of note, in 2013 the operator conducted a PM10 monitoring campaign within the ODSRVA using 

non-FEM, MetOne E-BAM monitors. The PM10 levels observed within the ODSVRA were generally 

much higher than those recorded downwind at our CDF and Mesa2 SLAMS. Contractors for the 

operator also made several hundred emissivity measurements of the dune surface. Reports 

summarizing the results of these campaigns are available on the District website.5 

Price Canyon Monitoring 

The Price Canyon Oilfield is located in Price Canyon between Pismo Beach and the Edna Valley wine 

region, just south of the City of San Luis Obispo. This area has long been plagued by odors 

emanating from the field. Therefore, as a condition of a permit for expanded oilfield operations, 

SLOCAPCD is requiring on-site ambient hydrogen sulfide (H2S) monitoring. This is anticipated to 

begin by June 2015, and will employ a Thermo Scientific 450i H2S analyzer. SLOCAPCD will have 

access to raw data in real-time. There is currently no plan to submit this data to AQS. 

 

5

 San Luis Obispo County Air Pollution Control District, “Coastal Dunes Rule 1001,” 

http://slocleanair.org/air/pmstudydata.php. 
18 

Air Quality Data 

All of the SLAMS monitoring stations currently operating in the County are registered with the EPA 

and ARB and regularly report data to the EPA’s AQS database, ARB’s AQMIS2 website, and the 

airnow.gov website. Validated data from sites operated by SLOCAPCD are always submitted to AQS 

by end of the quarter following the quarter in which they were collected; usually data is submitted 

well before this deadline. Raw data is uploaded automatically to AQMIS and airnow.gov typically 

within an hour after being generated in the field. In addition, raw data for the current day and 

previous day is available on the SLOCAPCD website. All data generated at these stations are public 

information and are available in various formats. Table 3, below, lists some popular sources for 

these data. 

SLOCAPCD, and when applicable ARB, regularly submit precision and accuracy data to AQS for all 

gaseous and particulate pollutants measured in the network. Additionally, in accordance with 40 CFR 

58.15, SLOCAPCD certifies its AQS dataset for the previous year every spring. SLOCAPCD submitted a 

certification package for calendar year 2014 data to EPA on April 7, 2015. 

Table 3: Sources for Air Quality Data from San Luis Obispo 

Agency Address for Data Requests Website for 

Data Access 

Data Available Online

SLOCAPCD 3433 Robert Ct., 

San Luis Obispo, CA 93401 

www.slocleanair.org/

air/lasthour.php

Raw data from last 24 to 48 

hours. Only sites operated by 

SLOCAPCD. 

ARB P.O. Box 2815 

Sacramento, CA 95812 

AQMIS2: 

www.arb.ca.gov/aqmi

s2/aqdselect.php

ADAM: 

www.arb.ca.gov/ada

m/

Most California sites, including 

all sites in San Luis Obispo 

County. Real-time raw data 

and archived validated data. 

EPA Ariel Rios Building 

1200 Pennsylvania Ave NW 

Washington, DC 20460 

AQS:

www.epa.gov/ttn/airs

/airsaqs/detaildata

 

Validated data from across the 

U.S. Typically one to several 

months behind current date. 

AirNow.gov U.S. EPA – OAQPS – ITG

Mail Code E143-03 

Research Triangle Park, NC 

27711 

www.airnow.gov Current air quality conditions, 

nationwide. Based on real 

time, raw data. 

 
19 

Appendix A: Minimum Monitoring Requirements The SLOCAPCD monitoring network meets the minimum monitoring requirements for all criteria pollutants as establ

The tables below list the criteria used to determine compliance with Federal regulations. The County population cited (269,637) is from the 2010 census; the California Department of Finance estimates the population to be 272,357 as o

Using this figure in lieu of the official census number does not change the required number of sites for any pollutant

Minimum Monitoring Requirements for Ozone (O3) 

MSA County Population (Census Year) 8-hour Design Value (years)a Design Value Site Name (AQS ID) 

Number of 

Required 

Sitesb 

N

of 

San Luis ObispoPaso Robles San Luis Obispo 269,637 (2010) 76 ppb (2012-14) Red Hills (06-079-8005) 1 

a This Design Value is for eastern San Luis Obispo County, which in early 2012 was designated as marginally non-atta

8-hour ozone standard. The design value for the rest of the county is 63 ppb (2012-14), and the corresponding design 

Atascadero (06-079-8001). 

b Refer to section 4.1 and Table D-2 of Appendix D to 40 CFR Part 58 for requirements. 

Monitors required for SIP or Maintenance Plan: None 

6 California Department of Finance, “E-1, Current Population Estimates,” May 1, 2014. 

http://www.dof.ca.gov/research/demographic/reports/estimates/e-1/view.php
20 

Minimum Monitoring Requirements for PM2.5 SLAMs 

MSA County 

Population 

(Census 

Year) 

Annual 

Design 

Value 

(years) 

Annual 

Design Value 

Site

(AQS ID) 

Daily 

Design 

Value 

(years) 

Daily Design 

Value Site 

Name 

(AQS ID) 

Number of 

Required 

SLAMS 

Sitesa 

San Luis 

Obispo-Paso 

Robles 

San Luis 

Obispo 

269,637 

(2010) 

11.6 g/m3

(2012-14) 

CDF

(06-079-2007) 

30 g/m3

(2012-14) 

CDF 

(06-079-2007) 

1 

a Refer to section 4.7.1 and Table D-5 of Appendix D to 40 CFR Part 58 for requirements. 

Monitors required for SIP or Maintenance Plan: None 

Minimum Monitoring Requirements for Continuous PM2.5 Monitors 

MSA County 

Population 

(Census 

Year) 

Annual 

Design 

Value 

(years) 

Annual 

Design Value 

Site 

(AQS ID) 

Daily 

Design 

Value 

(years) 

Daily Design 

Value Site 

Name 

(AQS ID) 

Number of 

Required 

Continuous 

Monitorsa 

Nu

A

Con

M

San Luis 

Obispo -

Paso Robles 

San Luis 

Obispo 

269,637 

(2010) 

11.6 g/m3

(2012-14) 

CDF 

(06-079-2007) 

30 g/m3

(2012-14) 

CDF 

(06-079-2007) 

1 

a Refer to section 4.7.2 and Table D-5 of Appendix D to 40 CFR Part 58 for requirements. 

Monitors required for SIP or Maintenance Plan: None 
21 

Minimum Monitoring Requirements for PM10 

MSA County Population (Census Year)

Maximum 

Concentration 

(Year)

Maximum 

Concentration Site 

Name (AQS ID) 

Number of 

Required 

Sitesa 

N

of 

San Luis ObispoPaso Robles San Luis Obispo 269,637 (2010) 165 g/m3 (2014) CDF (06-079-2007) 1-2 

a Refer to section 4.6 and Table D-4 of Appendix D to 40 CFR Part 58 for requirements. 

Monitors required for SIP or Maintenance Plan: None 

Minimum Monitoring Requirements for Nitrogen Dioxide (NO2) 

CBSA 

Population 

(Census 

Year) 

Maximum 

AADT Count 

(Years)

Number of 

Required 

Near-road 

Monitorsa 

Number of 

Active 

Near-road 

Monitors 

Number of 

Additional 

Near-road 

Monitors 

Needed 

Number of 

Required 

Area-wide 

Monitorsa 

N

of 

Ar

M

San Luis ObispoPaso Robles 269,637 (2010) 76,000 (2013) 0 0 0 0 

a Refer to section 4.3 of Appendix D to 40 CFR Part 58 for requirements. 

Monitors required for SIP or Maintenance Plan: None Monitors required for PAMS: None EPA Regional Administrator-required monitors per 40 CFR 58, App. D 4.3.4: None 
22 

Minimum Monitoring Requirements for Sulfur Dioxide (SO2) 

CBSA County 

Population 

(Census 

Year)

Total SO2a

(Tons/year)

Population Weighted 

Emissions Index 

(million persontons/year)b 

Number of 

Required 

Monitorsc 

Number of 

Active 

Monitors

San Luis ObispoPaso Robles San Luis Obispo 269,637 (2010) 272 73 0 1 

a From the 2011 National Emissions Inventory. http://www.epa.gov/ttn/chief/net/2011inventory.htmlb Product of CBSA population and SO2 emissions, divided by one million. c Refer to section 4.4 of Appendix D to 40 CFR Part 58 for requirements. 

Monitors required for SIP or Maintenance Plan: None 

Minimum Monitoring Requirements for Carbon Monoxide (CO) 

CBSA 

Population 

(Census 

Year)

Number of Required 

Near-Road Monitorsa 

Number of Active 

Near-Road Monitors

Number of Additional 

Monitors Needed 

San Luis ObispoPaso Robles 269,637 (2010) 0 0 0 

a Refer to section 4.2 of Appendix D to 40 CFR Part 58 for requirements. 

Monitors required for SIP or Maintenance Plan: None EPA Regional Administrator-required monitors per section 4.2.2. of Appendix D to 40 CFR 58: None 
23 

Minimum Monitoring Requirements for Lead (Pb) at NCore 

NCore Site CBSA Population 

(Census Year)

Number of 

Required Monitorsa 

Number of Active 

Monitors

N

none San Luis ObispoPaso Robles 269,637 (2010) 0 0 

a Refer to section 4.5 of Appendix D to 40 CFR Part 58 for requirements. Source-Oriented Lead Monitoring (Including Airports) 

Source Address 

Pb Emissions 

(Tons/yr)

Emissions 

Inventory Source 

Data (Year)

Max 

3-Month 

Design Value 

Design 

Value 

Date 

Number of 

Required 

Monitorsa 

Numb

of Acti

Monito

none n/a n/a n/a n/a n/a 0 0 

a Refer to section 4.5 of Appendix D to 40 CFR Part 58 for requirements. 

Monitors required for SIP or Maintenance Plan: None EPA Regional Administrator-required monitors per section 4.5(c) of Appendix D to 40 CFR 58: None 
24 

Appendix B: Collocation Requirements 

Particulate monitoring (PM10, PM2.5, and lead) is subject to the collocation requirements described in 

section 3 of Appendix A to 40 CFR 58. The requirements apply at the PQAO level, and SLOCAPCD is 

part of the ARB PQAO. All particulate monitors in San Luis Obispo County are MetOne 1020 Beta 

Attenuation Monitors (BAMs). These are continuous FEM instruments (PM10 method code: 122; PM2.5

method code: 170). There are no collocated particulate monitors within the SLOCAPCD network; 

however as described below, there are collocated monitors within the ARB PQAO. 

It is unknown whether collocation requirements for PM2.5 are being met at the statewide PQAO level. 

According to ARB’s most recent Annual Monitoring Report for Small Districts in California,7

 in 2013 

there were 32 active PM2.5 FEM BAM 1020 monitors (method 170) in the PQAO; thus five collocated 

monitors were needed: three FRM/FEM pairs and two FEM/FEM pairs. The report indicates that the 

ARB PQAO met the minimum FEM/FEM collocation requirements for its network, but needed to add 

a collocated FRM/FEM pair. The report discusses plans for establishing the needed FRM/FEM pair at 

the Madera site, and AQS shows an FRM reporting at this site starting in June 2014. Thus it would 

appear that the collocation requirement has been satisfied, though it is also possible that additional 

method 170 monitors have come online since then, triggering the need for additional collocated 

monitors. An AQS Certification and Concurrence Report (AMP600) for 2014 (executed in March 

2015), reported a slightly different number of monitors, and also indicated that collocation 

requirements were not being met for that year. See Table B-1 below. 

With regard to PM10 monitoring, all monitors in the District are continuous FEM BAMs, and thus 

there are no collocation requirements. Finally, lead monitoring is not done in the County, and thus 

there is no collocation requirement. 

Table B- 1: Collocation Requirements for PM2.5, Method Code 170 

Data 

Source 

(see text) 

Number of 

Primary 

Monitors 

Number of 

Required 

Collocated 

Monitors 

Number of 

Active 

Collocated FRM 

Monitors 

Number of Active 

Collocated FEM 

Monitors (same method 

designation as primary) 

ARB 32 5 2 2 

AMP600 33 5 4 total collocated monitors, type not indicated

 

7

 Air Resources Board, “Annual Monitoring Network Report for Twenty-three Districts in California,” 

June 2014. http://www.arb.ca.gov/aqd/amnr/amnr2014draft.pdf. 
25 

Appendix C: Detailed Site Information 

Local site name Paso Robles

AQS ID 06-079-0005

GPS coordinates (decimal degrees) 35.61467, -120.65691 

Street Address 235 Santa Fe Ave, Paso Robles 

County San Luis Obispo

Distance to roadways (meters) 27 to Santa Fe Ave.

110 to Sherwood Rd. 

180 to Creston Rd. 

2700 to US 101 

Traffic count (AADT, year) Santa Fe Ave.: 75 (estimated) 

Sherwood Rd.: 10,000 (2008) 

Creston Rd: 5,500 (2008) 

US101: 36,300 (2013) 

Groundcover (e.g. asphalt, dirt, sand) Asphalt

Representative statistical area name (i.e. MSA, CBSA, 

other) 

San Luis Obispo – Paso Robles 

(MSA) 

Pollutant, POC Ozone, 1 PM10, 2 

Primary / QA Collocated / Other N/A Primary 

Parameter code 44201 81102 

Basic monitoring objective(s) NAAQS

Comparison 

Public info, NAAQS

Comparison 

Site type(s) Population 

Exposure 

Population 

Exposure 

Monitor type(s) SLAMS SLAMS 

Network Affiliation N/A N/A 

Instrument manufacturer and model API 400E MetOne BAM 1020 

Method code 087 122 

FRM/FEM/ARM/other FEM FEM 

Collecting Agency ARB ARB 

Analytical Lab (i.e. weigh lab, toxics lab, other) N/A N/A 

Reporting Agency ARB ARB 

Spatial scale (e.g. micro, neighborhood) Neighborhood Neighborhood

Monitoring start date (MM/DD/YYYY) 09/01/1991 06/01/2013 a

Current sampling frequency (e.g. 1:3, continuous) continuous continuous

Calculated sampling frequency (e.g. 1:3/1:1) continuous continuous

Sampling season (MM/DD-MM/DD) 01/01-12/31 01/01-12/31

Probe height (meters) 6.2 5.2 

Distance from supporting structure (meters) 2.9 1.9 

Distance from obstructions on roof (meters) N/A N/A 

Distance from obstructions not on roof (meters) N/A N/A 

Distance from trees (meters) N/A N/A 

Distance to furnace or incinerator flue (meters) N/A N/A 

Distance between monitors fulfilling a QA Collocation 

requirement (meters) 

N/A N/A 
26 

Local site name Paso Robles

For low volume PM instruments, is any PM 

instrument within 1 m of the instrument? 

N/A No 

For high volume PM instruments, is any PM 

instrument within 2m of the instrument? 

N/A N/A 

Unrestricted airflow (degrees) 360 360 

Probe material for reactive gases (e.g. Pyrex, stainless 

steel, Teflon) 

Teflon N/A 

Residence time for reactive gases (seconds) 13.9 N/A 

Will there be changes within the next 18 months? No No 

Is it suitable for comparison against the annual 

PM2.5? 

N/A N/A 

Frequency of flow rate verification for manual PM 

samplers 

N/A N/A 

Frequency of flow rate verification for automated PM 

analyzers 

N/A bi-weekly 

Frequency of one-point QC check for gaseous 

instruments 

daily N/A 

Date of 2014 Annual Performance Evaluation for 

gaseous parameters 

11/18/2014b

12/18/2014c 

N/A 

Dates of 2014 Semi-Annual Flow Rate Audits for PM 

monitors 

N/A 5/14/2014 

12/18/2014 a This instrument did not begin reporting PM10-standard (88102) until 06/01/2013, but has been 

reporting PM10-actual (85101) since 08/11/2009. 

b Performed by ARB. 

c Performed by EPA. 

 
27 

Local site name Grover Beach

AQS ID 06-079-2001

GPS coordinates (decimal degrees) 35.12393, -120.63222 

Street Address 9 Le Sage Drive, Grover Beach 

County San Luis Obispo

Distance to roadways (meters) 10 to Le Sage Drive 

120 to US 1 

Traffic count (AADT, year) Le Sage: 300 (estimated) 

US 1: 9000 (2013) 

Groundcover (e.g. asphalt, dirt, sand) Cement and dirt

Representative statistical area name (i.e. MSA, CBSA, 

other) 

San Luis Obispo – Paso Robles 

(MSA) 

Pollutant, POC None (this is meteorology-only station)

 
28 

Local site name Mesa2

AQS ID 06-079-2004

GPS coordinates (decimal degrees) 35.02079, -120.56389

Street Address 1300 Guadalupe Rd., Nipomo 

County San Luis Obispo

Distance to roadways (meters) 40 to Guadalupe Rd. (US 1) 

Traffic count (AADT, year) Guadalupe Rd. (US 1): 6000 (2013) 

Groundcover (e.g. asphalt, dirt, sand) Vegetative

Representative statistical area name (i.e. MSA, 

CBSA, other) 

San Luis Obispo – Paso Robles 

(MSA) 

Pollutant, POC SO2, 1 PM2.5, 1 PM10, 3

Primary / QA Collocated / Other N/A Primary Primary

Parameter code 42401 88101 81102

Basic monitoring objective(s) NAAQS 

Comparison 

NAAQS 

Comparison 

NAAQS 

Comparison 

Site type(s) Source 

Oriented, Max 

Concentration

Source 

Oriented 

Source 

Oriented 

Monitor type(s) SLAMS SLAMS SLAMS

Network Affiliation N/A N/A N/A 

Instrument manufacturer and model API T100U MetOne BAM 

1020 

MetOne BAM 

1020 

Method code 100 170 122 

FRM/FEM/ARM/other FEM FEM FEM 

Collecting Agency SLOCAPCD SLOCAPD SLOCAPCD

Analytical Lab (i.e. weigh lab, toxics lab, other) N/A N/A N/A 

Reporting Agency SLOCAPCD SLOCAPCD SLOCAPCD

Spatial scale (e.g. micro, neighborhood) Middle Neighborhood Neighborhood

Monitoring start date (MM/DD/YYYY) 05/01/1989 07/01/2009 07/01/2009

Current sampling frequency (e.g. 1:3, 

continuous) 

continuous continuous continuous

Calculated sampling frequency (e.g. 1:3/1:1) continuous continuous continuous

Sampling season (MM/DD-MM/DD) 01/01-12/31 01/01-12/31 01/01-12/31

Probe height (meters) 4.8 4.8 4.8 

Distance from supporting structure (meters) 1.3 1.3 1.3 

Distance from obstructions on roof (meters) N/A N/A N/A 

Distance from obstructions not on roof 

(meters) 

N/A N/A N/A 

Distance from trees (meters) N/A N/A N/A 

Distance to furnace or incinerator flue 

(meters) 

N/A N/A N/A 

Distance between monitors fulfilling a QA 

Collocation requirement (meters) 

N/A N/A N/A 

For low volume PM instruments, is any PM 

instrument within 1 m of the instrument? 

N/A No No 

For high volume PM instruments, is any PM N/A N/A N/A 
29 

Local site name Mesa2

instrument within 2m of the instrument?

Unrestricted airflow (degrees) 360 360 360 

Probe material for reactive gases (e.g. Pyrex, 

stainless steel, Teflon) 

Teflon N/A N/A 

Residence time for reactive gases (seconds) 8.1 N/A N/A 

Will there be changes within the next 18 

months? 

No No No 

Is it suitable for comparison against the annual 

PM2.5? 

N/A Yes N/A 

Frequency of flow rate verification for manual 

PM samplers 

N/A N/A N/A 

Frequency of flow rate verification for 

automated PM analyzers 

N/A bi-weekly bi-weekly

Frequency of one-point QC check for gaseous 

instruments 

daily N/A N/A 

Date of 2014 Annual Performance Evaluation 

for gaseous parameters 

5/20/2014 N/A N/A 

Dates of 2014 Semi-Annual Flow Rate Audits 

for PM monitors 

N/A 5/20/2014 

10/30/2014 

5/20/2014

10/30/2014 

 
30 

Local site name San Luis Obispo

AQS ID 06-079-2006

GPS coordinates (decimal degrees) 35.25651, -120.66945

Street Address 3220 South Higuera St., San Luis Obispo

County San Luis Obispo

Distance to roadways (meters) 57 to South Higuera St.

450 to US 101 

Traffic count (AADT, year) South Higuera St.: 13,980 (2012) 

US 101: 58,600 (2013) 

Groundcover (e.g. asphalt, dirt, sand) Vegetative

Representative statistical area name (i.e. MSA, 

CBSA, other) 

San Luis Obispo – Paso Robles 

(MSA) 

Pollutant, POC O3, 1 PM2.5, 3 PM10, 2

Primary / QA Collocated / Other N/A Primary Primary

Parameter code 44201 88101 81102

Basic monitoring objective(s) NAAQS 

Comparison 

NAAQS 

Comparison 

NAAQS 

Comparison, 

Public Info 

Site type(s) Population 

Exposure 

General/ 

Background 

Population 

Exposure 

Monitor type(s) SLAMS SLAMS SLAMS

Network Affiliation N/A N/A N/A 

Instrument manufacturer and model API T400 MetOne BAM 

1020 

MetOne BAM 

1020 

Method code 087 170 122 

FRM/FEM/ARM/other FEM FEM FEM 

Collecting Agency ARB ARB ARB 

Analytical Lab (i.e. weigh lab, toxics lab, other) N/A N/A N/A 

Reporting Agency ARB ARB ARB 

Spatial scale (e.g. micro, neighborhood) Neighborhood Neighborhood Neighborhood

Monitoring start date (MM/DD/YYYY) 09/21/2005 03/15/2011 06/01/2013 a

Current sampling frequency (e.g. 1:3, 

continuous) 

continuous continuous continuous

Calculated sampling frequency (e.g. 1:3/1:1) continuous continuous continuous

Sampling season (MM/DD-MM/DD) 01/01-12/31 01/01-12/31 01/01-12/31

Probe height (meters) 12.8 12.8 12.8 

Distance from supporting structure (meters) 1.8 2.0 2.0 

Distance from obstructions on roof (meters) N/A N/A N/A 

Distance from obstructions not on roof 

(meters) 

N/A N/A N/A 

Distance from trees (meters) N/A N/A N/A 

Distance to furnace or incinerator flue 

(meters) 

N/A N/A N/A 

Distance between monitors fulfilling a QA 

Collocation requirement (meters) 

N/A N/A N/A 

For low volume PM instruments, is any PM N/A No No 
31 

Local site name San Luis Obispo

instrument within 1 m of the instrument? 

For high volume PM instruments, is any PM 

instrument within 2m of the instrument? 

N/A N/A N/A 

Unrestricted airflow (degrees) 360 360 360 

Probe material for reactive gases (e.g. Pyrex, 

stainless steel, Teflon) 

Teflon N/A N/A 

Residence time for reactive gases (seconds) 8.7 N/A N/A 

Will there be changes within the next 18 

months? 

No No No 

Is it suitable for comparison against the 

annual PM2.5? 

N/A Yes N/A 

Frequency of flow rate verification for manual 

PM samplers 

N/A N/A N/A 

Frequency of flow rate verification for 

automated PM analyzers 

N/A bi-weekly bi-weekly

Frequency of one-point QC check for gaseous 

instruments 

daily N/A N/A 

Date of 2014 Annual Performance Evaluation 

for gaseous parameters 

11/18/2014 N/A N/A 

Dates of 2014 Semi-Annual Flow Rate Audits 

for PM monitors 

N/A 5/14/2014 

11/18/2014 

5/14/2014

11/18/2014 a This instrument did not begin reporting PM10-standard (88102) until 06/01/2013, but has been 

reporting PM10-actual (85101) since 03/15/2011 as 06-079-2006-85101-3. 

 
32 

Local site name CDF

AQS ID 06-079-2007

GPS coordinates (decimal degrees) 35.04673, -120.58777 

Street Address 2391 Willow Rd., Arroyo Grande 

County San Luis Obispo

Distance to roadways (meters) 53 to Willow Rd. (US 1). 

Traffic count (AADT, year) Willow Rd. (US1): 6,500 

Groundcover (e.g. asphalt, dirt, sand) Vegetative, Sand

Representative statistical area name (i.e. MSA, CBSA, 

other) 

San Luis Obispo – Paso Robles 

(MSA) 

Pollutant, POC PM2.5, 1 PM10, 2 

Primary / QA Collocated / Other Primary Primary 

Parameter code 44201 81102 

Basic monitoring objective(s) NAAQS 

Comparison 

NAAQS 

Comparison 

Site type(s) Max 

Concentration, 

Source Oriented 

Max 

Concentration, 

Source Oriented 

Monitor type(s) SLAMS SLAMS 

Network Affiliation N/A N/A 

Instrument manufacturer and model MetOne BAM 1020 MetOne BAM 1020 

Method code 170 122 

FRM/FEM/ARM/other FEM FEM 

Collecting Agency SLOCAPCD SLOCAPCD

Analytical Lab (i.e. weigh lab, toxics lab, other) N/A N/A 

Reporting Agency SLOCAPCD SLOCAPCD

Spatial scale (e.g. micro, neighborhood) Neighborhood Neighborhood

Monitoring start date (MM/DD/YYYY) 08/01/2010 01/01/2010

Current sampling frequency (e.g. 1:3, continuous) continuous continuous

Calculated sampling frequency (e.g. 1:3/1:1) continuous continuous

Sampling season (MM/DD-MM/DD) 01/01-12/31 01/01-12/31

Probe height (meters) 4.0 4.0 

Distance from supporting structure (meters) 1.4 1.4 

Distance from obstructions on roof (meters) N/A N/A 

Distance from obstructions not on roof (meters) N/A N/A 

Distance from trees (meters) N/A N/A 

Distance to furnace or incinerator flue (meters) N/A N/A 

Distance between monitors fulfilling a QA Collocation 

requirement (meters) 

N/A N/A 

For low volume PM instruments, is any PM 

instrument within 1 m of the instrument? 

N/A No 

For high volume PM instruments, is any PM 

instrument within 2m of the instrument? 

N/A N/A 

Unrestricted airflow (degrees) 360 360 

Probe material for reactive gases (e.g. Pyrex, stainless 

steel, Teflon) 

N/A N/A 
33 

Local site name CDF

Residence time for reactive gases (seconds) N/A N/A 

Will there be changes within the next 18 months? No No 

Is it suitable for comparison against the annual 

PM2.5? 

Yes N/A 

Frequency of flow rate verification for manual PM 

samplers 

N/A N/A 

Frequency of flow rate verification for automated PM 

analyzers 

bi-weekly bi-weekly 

Frequency of one-point QC check for gaseous 

instruments 

N/A N/A 

Date of 2014 Annual Performance Evaluation for 

gaseous parameters 

N/A N/A 

Dates of 2014 Semi-Annual Flow Rate Audits for PM 

monitors 

5/20/2014

10/30/2014 

5/20/2014 

10/30/2014 

 
34 

Local site name Morro Bay

AQS ID 06-079-3001

GPS coordinates (decimal degrees) 35.36640, -120.84268

Street Address 899 Morro Bay Blvd., Morro Bay 

County San Luis Obispo

Distance to roadways (meters) 37 to Morro Bay Blvd. 

220 to CA 1 

Traffic count (AADT, year) Morro Bay Blvd.: 12,400 (2006) 

CA 1: 20,600 (2013) 

Groundcover (e.g. asphalt, dirt, sand) Paved

Representative statistical area name (i.e. MSA, 

CBSA, other) 

San Luis Obispo – Paso Robles 

(MSA) 

Pollutant, POC O3, 1 NO2, 1 

Primary / QA Collocated / Other N/A Primary 

Parameter code 44201 42602 

Basic monitoring objective(s) NAAQS Comparison NAAQS Comparison

Site type(s) General/Background General/Background

Monitor type(s) SLAMS SLAMS 

Network Affiliation N/A N/A 

Instrument manufacturer and model API 400A API T200U 

Method code 087 599 

FRM/FEM/ARM/other FEM FRM 

Collecting Agency SLOCAPCD SLOCAPCD 

Analytical Lab (i.e. weigh lab, toxics lab, other) N/A N/A 

Reporting Agency SLOCAPCD SLOCAPCD 

Spatial scale (e.g. micro, neighborhood) Regional Neighborhood

Monitoring start date (MM/DD/YYYY) 01/01/1981 06/01/2001 

Current sampling frequency (e.g. 1:3, continuous) continuous continuous 

Calculated sampling frequency (e.g. 1:3/1:1) continuous continuous 

Sampling season (MM/DD-MM/DD) 01/01-12/31 01/01-12/31

Probe height (meters) 4.0 4.0 

Distance from supporting structure (meters) 1.4 1.4 

Distance from obstructions on roof (meters) N/A N/A 

Distance from obstructions not on roof (meters) N/A N/A 

Distance from trees (meters) N/A N/A 

Distance to furnace or incinerator flue (meters) N/A N/A 

Distance between monitors fulfilling a QA 

Collocation requirement (meters) 

N/A N/A 

For low volume PM instruments, is any PM 

instrument within 1 m of the instrument? 

N/A N/A 

For high volume PM instruments, is any PM 

instrument within 2m of the instrument? 

N/A N/A 

Unrestricted airflow (degrees) 360 360 

Probe material for reactive gases (e.g. Pyrex, 

stainless steel, Teflon) 

Teflon Teflon 
35 

Local site name Morro Bay

Residence time for reactive gases (seconds) 7.6 7.0 

Will there be changes within the next 18 months? No No 

Is it suitable for comparison against the annual 

PM2.5? 

N/A N/A 

Frequency of flow rate verification for manual PM 

samplers 

N/A N/A 

Frequency of flow rate verification for automated 

PM analyzers 

N/A N/A 

Frequency of one-point QC check for gaseous 

instruments 

daily daily 

Date of 2014 Annual Performance Evaluation for 

gaseous parameters 

03/12/2014 03/12/2014 

Dates of 2014 Semi-Annual Flow Rate Audits for PM 

monitors 

N/A N/A 

 
36 

Local site name Nipomo Regional Park (NRP) 

AQS ID 06-079-4002

GPS coordinates (decimal degrees) 35.03150, -120.50101

Street Address W. Tefft St. and Pomeroy Rd., Nipomo 

County San Luis Obispo

Distance to roadways (meters) 500 To Tefft St.

240 to Pomeroy Rd. 

Traffic count (AADT, year) Tefft St.: 1,500 (2009)

Pomeroy Rd.: 6400 (2008) 

Groundcover (e.g. asphalt, dirt, sand) Vegetative

Representative statistical area name (i.e. MSA, 

CBSA, other) 

San Luis Obispo – Paso Robles 

(MSA) 

Pollutant, POC O3, 1 NO2, 1 PM10, 2

Primary / QA Collocated / Other N/A Primary Primary

Parameter code 44201 42602 81102

Basic monitoring objective(s) NAAQS 

Comparison 

NAAQS 

Comparison 

NAAQS 

Comparison 

Site type(s) General/ 

Background 

General/ 

Background 

General/ 

Background 

Monitor type(s) SLAMS SLAMS SLAMS

Network Affiliation N/A N/A N/A 

Instrument manufacturer and model API 400E API T200U MetOne BAM 

1020 

Method code 087 599 122 

FRM/FEM/ARM/other FEM FRM FEM 

Collecting Agency SLOCAPCD SLOCAPCD SLOCAPCD

Analytical Lab (i.e. weigh lab, toxics lab, other) N/A N/A N/A 

Reporting Agency SLOCAPCD SLOCAPCD SLOCAPCD

Spatial scale (e.g. micro, neighborhood) Regional Regional Regional

Monitoring start date (MM/DD/YYYY) 11/01/1998 11/01/1998 05/16/2010

Current sampling frequency (e.g. 1:3, 

continuous) 

continuous continuous continuous

Calculated sampling frequency (e.g. 1:3/1:1) continuous continuous continuous

Sampling season (MM/DD-MM/DD) 01/01-12/31 01/01-12/31 01/01-12/31

Probe height (meters) 4.0 4.0 4.7 

Distance from supporting structure (meters) 1.0 1.0 1.7 

Distance from obstructions on roof (meters) N/A N/A N/A 

Distance from obstructions not on roof 

(meters) 

N/A N/A N/A 

Distance from trees (meters) N/A N/A N/A 

Distance to furnace or incinerator flue 

(meters) 

N/A N/A N/A 

Distance between monitors fulfilling a QA 

Collocation requirement (meters) 

N/A N/A N/A 

For low volume PM instruments, is any PM 

instrument within 1 m of the instrument? 

N/A N/A No 
37 

Local site name Nipomo Regional Park (NRP) 

For high volume PM instruments, is any PM 

instrument within 2m of the instrument? 

N/A N/A N/A 

Unrestricted airflow (degrees) 360 360 360 

Probe material for reactive gases (e.g. Pyrex, 

stainless steel, Teflon) 

Teflon Teflon N/A 

Residence time for reactive gases (seconds) 7.4 8.4 N/A 

Will there be changes within the next 18 

months? 

No No No 

Is it suitable for comparison against the 

annual PM2.5? 

N/A N/A N/A 

Frequency of flow rate verification for manual 

PM samplers 

N/A N/A N/A 

Frequency of flow rate verification for 

automated PM analyzers 

N/A N/A bi-weekly

Frequency of one-point QC check for gaseous 

instruments 

daily daily N/A 

Date of 2014 Annual Performance Evaluation 

for gaseous parameters 

05/20/2014 05/20/2014 N/A 

Dates of 2014 Semi-Annual Flow Rate Audits 

for PM monitors 

N/A N/A 5/20/2014

10/30/2014 

 
38 

Local site name Atascadero (original site)

AQS ID 06-079-8001

GPS coordinates (decimal degrees) 35.49153, -120.66799

Street Address 6005 Lewis Ave., Atascadero, CA

County San Luis Obispo

Distance to roadways (meters) 62 to Traffic Way

68 to Lewis Ave. 

400 to US 101 

500 to CA 41 

Traffic count (AADT, year) Traffic Way: < 7,400 (2014) a

Lewis Ave.: < 2,500 (2014) a 

US 101: 58,600 (2013) 

CA 41: 10,400 (2013) 

Groundcover (e.g. asphalt, dirt, sand) Asphalt

Representative statistical area name (i.e. 

MSA, CBSA, other) 

San Luis Obispo – Paso Robles

(MSA) 

Pollutant, POC O3, 1 NO2, 1 PM2.5, 3 PM10, 3

Primary / QA Collocated / Other N/A Primary Primary Primary

Parameter code 44201 42602 88101 81102

Basic monitoring objective(s) NAAQS 

Comparison 

NAAQS 

Comparison 

NAAQS 

Comparison 

NAAQS 

Comparison 

Site type(s) Population 

Exposure, Max 

Concentration 

Population 

Exposure, Max 

Concentration 

Population 

Exposure 

Population 

Exposure 

Monitor type(s) SLAMS SLAMS SLAMS SLAMS

Network Affiliation N/A N/A N/A N/A

Instrument manufacturer and model API T400 API T200 MetOne BAM 

1020 

MetOne BAM 

1020 

Method code 087 099 170 122

FRM/FEM/ARM/other FEM FRM FEM FEM

Collecting Agency SLOCAPCD SLOCAPCD SLOCAPCD SLOCAPCD

Analytical Lab (i.e. weigh lab, toxics lab, other) N/A N/A N/A N/A

Reporting Agency SLOCAPCD SLOCAPCD SLOCAPCD SLOCAPCD

Spatial scale (e.g. micro, neighborhood) Neighborhood Neighborhood Neighborhood Neighborhood

Monitoring start date (MM/DD/YYYY) 10/01/1988 08/01/1990 06/01/2009 09/07/2010

Current sampling frequency (e.g. 1:3, 

continuous) 

continuous continuous continuous continuous

Calculated sampling frequency (e.g. 1:3/1:1) continuous continuous continuous continuous

Sampling season (MM/DD-MM/DD) 01/01-12/31 01/01-12/31 01/01-12/31 01/01-12/31

Probe height (meters) 5.0 5.0 5.8 5.3

Distance from supporting structure (meters) 1.4 1.4 2.2 1.7

Distance from obstructions on roof (meters) N/A N/A N/A N/A

Distance from obstructions not on roof 

(meters) 

N/A N/A N/A N/A

Distance from trees (meters) N/A N/A N/A N/A

Distance to furnace or incinerator flue N/A N/A N/A N/A
39 

Local site name Atascadero (original site)

(meters) 

Distance between monitors fulfilling a QA 

Collocation requirement (meters) 

N/A N/A N/A N/A

For low volume PM instruments, is any PM 

instrument within 1 m of the instrument? 

N/A N/A N/A No

For high volume PM instruments, is any PM 

instrument within 2m of the instrument? 

N/A N/A N/A N/A

Unrestricted airflow (degrees) 360 360 360 360

Probe material for reactive gases (e.g. Pyrex, 

stainless steel, Teflon) 

Teflon Teflon N/A N/A

Residence time for reactive gases (seconds) 9.5 8.1 N/A N/A

Will there be changes within the next 18 

months? 

No No No No

Is it suitable for comparison against the 

annual PM2.5? 

N/A N/A Yes N/A

Frequency of flow rate verification for manual 

PM samplers 

N/A N/A N/A N/A

Frequency of flow rate verification for 

automated PM analyzers 

N/A N/A bi-weekly bi-weekly

Frequency of one-point QC check for gaseous 

instruments 

daily daily N/A N/A

Date of 2014 Annual Performance Evaluation 

for gaseous parameters 

05/20/2014 05/20/2014 N/A N/A

Dates of 2014 Semi-Annual Flow Rate Audits 

for PM monitors 

N/A N/A 5/20/2014 

10/30/2014 

5/20/2014

10/30/2014 a

 Traffic counts were conducted only during peak morning and afternoon hours along these streets. 

Along this stretch of Traffic Way, a total of 1,233 vehicles were counted during these four hours, 

therefore six times this figure (7,398) represents the likely maximum AADT. Likewise, the vehicle 

count along Lewis Ave. during the four peak commute hours was 415, so 2,490 represents the likely 

maximum AADT. 

 
40 

Local site name Atascadero (new site)

AQS ID 06-079-8002

GPS coordinates (decimal degrees) 35.49453, -120.66617

Street Address 5599 Traffic Way, Atascadero, CA

County San Luis Obispo

Distance to roadways (meters) 163 to Traffic Way

770 to US 101 

330 to CA 41 

Traffic count (AADT, year) Traffic Way: < 7,400 (2014)a

US 101: 58,600 (2013) 

CA 41: 10,400 (2013) 

Groundcover (e.g. asphalt, dirt, sand) Vegetative

Representative statistical area name (i.e. 

MSA, CBSA, other) 

San Luis Obispo – Paso Robles

(MSA) 

Pollutant, POC O3, 1 NO2, 1 PM2.5, 3 PM10, 3

Primary / QA Collocated / Other N/A Primary Primary Primary

Parameter code 44201 42602 88101 81102

Basic monitoring objective(s) NAAQS 

Comparison 

NAAQS 

Comparison 

NAAQS 

Comparison 

NAAQS 

Comparison 

Site type(s) Population 

Exposure, Max 

Concentration 

Population 

Exposure, Max 

Concentration 

Population 

Exposure 

Population 

Exposure 

Monitor type(s) SLAMS SLAMS SLAMS SLAMS

Network Affiliation N/A N/A N/A N/A

Instrument manufacturer and model API T400 API T200 MetOne BAM 

1020 

MetOne BAM 

1020 

Method code 087 099 170 122

FRM/FEM/ARM/other FEM FRM FEM FEM

Collecting Agency SLOCAPCD SLOCAPCD SLOCAPCD SLOCAPCD

Analytical Lab (i.e. weigh lab, toxics lab, other) N/A N/A N/A N/A

Reporting Agency SLOCAPCD SLOCAPCD SLOCAPCD SLOCAPCD

Spatial scale (e.g. micro, neighborhood) Neighborhood Neighborhood Neighborhood Neighborhood

Monitoring start date (MM/DD/YYYY) 02/25/2015 02/25/2015 02/25/2015 02/25/2015

Current sampling frequency (e.g. 1:3, 

continuous) 

continuous continuous continuous continuous

Calculated sampling frequency (e.g. 1:3/1:1) continuous continuous continuous continuous

Sampling season (MM/DD-MM/DD) 01/01-12/31 01/01-12/31 01/01-12/31 01/01-12/31

Probe height (meters) 5.0 5.0 5.8 5.3

Distance from supporting structure (meters) 1.4 1.4 2.2 1.7

Distance from obstructions on roof (meters) N/A N/A N/A N/A

Distance from obstructions not on roof 

(meters) 

N/A N/A N/A N/A

Distance from trees (meters) N/A N/A N/A N/A

Distance to furnace or incinerator flue 

(meters) 

N/A N/A N/A N/A

Distance between monitors fulfilling a QA N/A N/A N/A N/A
41 

Local site name Atascadero (new site)

Collocation requirement (meters) 

For low volume PM instruments, is any PM 

instrument within 1 m of the instrument? 

N/A N/A N/A No

For high volume PM instruments, is any PM 

instrument within 2m of the instrument? 

N/A N/A N/A N/A

Unrestricted airflow (degrees) 360 360 360 360

Probe material for reactive gases (e.g. Pyrex, 

stainless steel, Teflon) 

Teflon Teflon N/A N/A

Residence time for reactive gases (seconds) 9.5 8.1 N/A N/A

Will there be changes within the next 18 

months? 

No No No No

Is it suitable for comparison against the 

annual PM2.5? 

N/A N/A Yes N/A

Frequency of flow rate verification for manual 

PM samplers 

N/A N/A N/A N/A

Frequency of flow rate verification for 

automated PM analyzers 

N/A N/A bi-weekly bi-weekly

Frequency of one-point QC check for gaseous 

instruments 

daily daily N/A N/A

Date of 2014 Annual Performance Evaluation 

for gaseous parameters 

N/A N/A N/A N/A

Dates of 2014 Semi-Annual Flow Rate Audits 

for PM monitors 

N/A N/A N/A N/A

a

 Traffic counts were conducted only during peak morning and afternoon hours along this street. 

Along this stretch of Traffic Way, a total of 1,233 vehicles were counted during these four hours, 

therefore six times this figure (7,398) represents the likely maximum AADT. 

 
42 

Local site name Red Hills

AQS ID 06-079-8005

GPS coordinates (decimal degrees) 35.64366, -120.23134 

Street Address 3601 Gillis Canyon Rd., Shandon 

County San Luis Obispo

Distance to roadways (meters) 100 to Gillis Canyon Rd. 

1740 to Bitterwater Rd. 

10,400 to CA 41 

Traffic count (AADT, year) Gillis Canyon Rd.: 23 (2008) 

BItterwater Rd.: 51 (2011) 

CA 41: 1,470 (2013) 

Groundcover (e.g. asphalt, dirt, sand) Vegetative

Representative statistical area name (i.e. MSA, 

CBSA, other) 

San Luis Obispo – Paso Robles 

(MSA) 

Pollutant, POC O3, 1

Primary / QA Collocated / Other N/A

Parameter code 44201

Basic monitoring objective(s) NAAQS Comparison

Site type(s) Regional Transport, Max Concentration

Monitor type(s) SLAMS

Network Affiliation N/A

Instrument manufacturer and model API T400

Method code 087

FRM/FEM/ARM/other FEM

Collecting Agency SLOCAPCD

Analytical Lab (i.e. weigh lab, toxics lab, other) N/A

Reporting Agency SLOCAPCD

Spatial scale (e.g. micro, neighborhood) Regional

Monitoring start date (MM/DD/YYYY) 07/01/2000

Current sampling frequency (e.g. 1:3, continuous) continuous

Calculated sampling frequency (e.g. 1:3/1:1) continuous

Sampling season (MM/DD-MM/DD) 01/01-12/31

Probe height (meters) 4.7

Distance from supporting structure (meters) 1.2

Distance from obstructions on roof (meters) N/A

Distance from obstructions not on roof (meters) N/A

Distance from trees (meters) N/A

Distance to furnace or incinerator flue (meters) N/A

Distance between monitors fulfilling a QA 

Collocation requirement (meters) 

N/A

For low volume PM instruments, is any PM 

instrument within 1 m of the instrument? 

N/A

For high volume PM instruments, is any PM 

instrument within 2m of the instrument? 

N/A

Unrestricted airflow (degrees) 360

Probe material for reactive gases (e.g. Pyrex, Teflon
43 

Local site name Red Hills

stainless steel, Teflon) 

Residence time for reactive gases (seconds) 10.1

Will there be changes within the next 18 months? No

Is it suitable for comparison against the annual 

PM2.5? 

N/A

Frequency of flow rate verification for manual PM 

samplers 

N/A

Frequency of flow rate verification for automated 

PM analyzers 

N/A

Frequency of one-point QC check for gaseous 

instruments 

daily

Date of 2014 Annual Performance Evaluation for 

gaseous parameters 

03/11/2014

Dates of 2014 Semi-Annual Flow Rate Audits for PM 

monitors 

N/A

 
44 

Local site name Carrizo Plains

AQS ID 06-079-8006

GPS coordinates (decimal degrees) 35.35474, -120.04013 

Street Address 9640 Carrizo Highway (CA 58), 

California Valley 

County San Luis Obispo

Distance to roadways (meters) 38 to Carrizo Highway (CA 58) 

Traffic count (AADT, year) Carrizo Highway (CA 58): 350 (2013)

Groundcover (e.g. asphalt, dirt, sand) Paved

Representative statistical area name (i.e. MSA, 

CBSA, other) 

San Luis Obispo – Paso Robles 

(MSA) 

Pollutant, POC O3, 1

Primary / QA Collocated / Other N/A

Parameter code 44201

Basic monitoring objective(s) NAAQS Comparison

Site type(s) Regional Transport, General Background

Monitor type(s) SLAMS

Network Affiliation N/A

Instrument manufacturer and model API 400A

Method code 087

FRM/FEM/ARM/other FEM

Collecting Agency SLOCAPCD

Analytical Lab (i.e. weigh lab, toxics lab, other) N/A

Reporting Agency SLOCAPCD

Spatial scale (e.g. micro, neighborhood) Regional

Monitoring start date (MM/DD/YYYY) 01/01/2006

Current sampling frequency (e.g. 1:3, continuous) continuous

Calculated sampling frequency (e.g. 1:3/1:1) continuous

Sampling season (MM/DD-MM/DD) 01/01-12/31

Probe height (meters) 4.7

Distance from supporting structure (meters) 1.1

Distance from obstructions on roof (meters) N/A

Distance from obstructions not on roof (meters) N/A

Distance from trees (meters) N/A

Distance to furnace or incinerator flue (meters) N/A

Distance between monitors fulfilling a QA 

Collocation requirement (meters) 

N/A

For low volume PM instruments, is any PM 

instrument within 1 m of the instrument? 

N/A

For high volume PM instruments, is any PM 

instrument within 2m of the instrument? 

N/A

Unrestricted airflow (degrees) 360

Probe material for reactive gases (e.g. Pyrex, 

stainless steel, Teflon) 

Teflon

Residence time for reactive gases (seconds) 15.7
45 

Local site name Carrizo Plains

Will there be changes within the next 18 months? No

Is it suitable for comparison against the annual 

PM2.5? 

N/A

Frequency of flow rate verification for manual PM 

samplers 

N/A

Frequency of flow rate verification for automated 

PM analyzers 

N/A

Frequency of one-point QC check for gaseous 

instruments 

daily

Date of 2014 Annual Performance Evaluation for 

gaseous parameters 

03/11/2014

Dates of 2014 Semi-Annual Flow Rate Audits for PM 

monitors 

N/A

 
46 

Appendix D: EPA Approval Atascadero Site Move 

This Appendix documents EPA’s approval the relocation of the Atascadero SLAMS from 6005 Lewis 

Avenue to 5599 Traffic Way. Figure D-1 is the email from Karl Tupper (SLOCAPCD) to Dena Vallano 

(EPA Region 9) requesting approval of the new site. Figure D-2 is the reply email from Dena Vallano 

granting approval. Email addresses and phone numbers have been redacted in these figures. Figure 

D-3 depicts the PowerPoint presentation referred to in the emails; a larger format version is 

available from the District upon request. 

Figure D-1: Email from Karl Tupper, SLOCAPCD, to Dena Vallano, EPA Region 9, requesting approval of 

new location for the Atascadero SLAMS. 
47 

Figure D-2: Reply email from Dena Vallano to Karl Tupper granting approval. 

 
48 

Figure D-3: PowerPoint presentation referred to in Figures D-1 and D-2. 

 
49 

Appendix E: Parallel Monitoring in Atascadero 

Introduction 

As noted earlier, in 2014 we were notified by the host of our Atascadero SLAMS that we needed to 

remove the station from their property (6005 Lewis Ave) in order to accommodate planned 

renovations and new construction. A potential new location was identified about 400 meters away at 

5599 Traffic Way, and a limited period of parallel monitoring was conducted at the original and 

potential sites to assess their comparability; ultimately the proposed site was chosen as the new 

location for the Atascadero SLAMS. Due to the timing of obtaining the needed equipment, getting 

site access, and the need to vacate the original site, parallel monitoring could only be conducted for 

limited time, specifically December 18, 2014 to February 23, 2015. Furthermore, due to equipment 

limitations, only ozone and PM2.5 could be monitored at the proposed site. All data collected at these 

sites is available upon request. 

Methods 

All instruments at the Lewis Ave site were housed within an insulated trailer; see the table in 

Appendix C for site 06-079-8001 for probe heights and other siting details. The trailer was equipped 

with a wall mounted air conditioning unit for climate control. Hourly room temperature was 

maintained between 20 and 30 o

C for the duration of the collocation period. At the Traffic Way site, 

the equipment was housed within a temporary enclosure measuring approximately 140 cm tall by 

70 cm wide and 70 cm deep. The PM2.5 probe was approximately 2.5 m above the ground and the 

ozone probe was at about 3 m; their inlets were less than 1 m apart. The enclosure was fitted with a 

small heater and two cooling fans, each controlled by its own thermostat. Most of the time, hourly 

average room temperature was maintained between 20 and 30 o

C, however 11 hours had average 

room temperatures between 30 and 33 o

C and 226 hours had average room temperatures between 

16 and 20 o

C. No data was invalidated based on shelter temperature, since it was always within the 

operating range of the instruments. 

At both locations ozone was monitored with Teledyne-API T400 photometric ozone analyzers. The 

Lewis Ave site monitor was operated in accordance with all QA/QC requirements in Appendix A of 

40 CFR 58. Nightly zero/span/precision checks during the parallel monitoring period yielded zero 

responses between 0 and 1.2 ppb, and precision errors between -1.2 and +1.6%; precision checks 

were carried out at approximately 62 ppb. In contrast, calibration equipment was not available for 

the Traffic Way site, so nightly zero/span/precision checks could not be performed. An initial start-up 

and a final shut-down calibration check were performed in the SLOCAPCD lab, and both gave 

passing results, with zero responses of 0 (start-up) and 0.4 (shut-down) and precision errors of 

+0.1% (start-up) and +0.9% (shut-down). The precision point for these calibrations was 

approximately 50 ppb. 

At both locations, PM2.5 was monitored using MetOne BAM 1020 instruments. While the Lewis Ave 

monitor was run as an FEM operated in accordance with all Appendix A QA/QC requirements, the 

Traffic Way monitor employed an SCC rather than a VSCC as the PM2.5 size selector. Bi-weekly QC 
50 

checks—consisting of leak checks, flow audits, temperature and pressure sensor checks, and time 

checks—were performed on both instruments, and both were subject to the same cleaning and 

preventative maintenance schedule. A 72-hr zero test was performed on the Traffic Way instrument 

prior to deployment. 

Analysis 

SLOCAPCD is not aware of any EPA requirements or guidelines for parallel monitoring; however 

ARB’s Air Monitoring Technical Advisory Committee (AMTAC) published guidelines in 1997.8

 Our 

analysis of the data is therefore informed by the AMTAC guidelines. 

Timing of Parallel Monitoring 

AMTAC recommends a year of parallel monitoring or at least monitoring during the season of 

highest expected concentration. A full year was not practical in this situation, and data was instead 

collected from December 18 through February 23. This period coincides with the season of highest 

expected PM2.5 concentration, which is December/January as shown below in Figure E-1. 

Unfortunately, ozone concentrations are typically at their lowest during this time of year, as shown 

in Figure E-2. 

 

8

 Air Monitoring Technical Advisory Committee, “Site Relocation and Parallel Monitoring Guidelines,” 

June 11, 1997. 
51 

Figure E-1: Monthly Average PM2.5 at Atascadero (Lewis Ave) as measured by BAM. 

Monthly Average PM2.5

PM2.5, ug/m3

Jan

FebMar

Apr

May

Jun

Jul

AugSep

Oct

NovDec

0 4 8 12 16 20

2014

2013

2012

2011

2010
52 

Figure E-2: Daily 8-hr Maximum Ozone by Month and Year at Atascadero (Lewis Ave). Solid lines connect 

the median values for each month; dotted lines connect the maximum values for each month. 

PM2.5 Analysis 

The analysis of PM2.5 was conducted using 24-hr averages. Only hours when both monitors had valid 

data were included in the averaging, and at least 18 valid hourly values were required for a 24-hr 

average to be valid. A scatterplot of these daily averages is shown in Figure E-3 along with the least 

squares fit. The R2

 of the least square fit is 0.95, suggesting that the relationship between the sites is 

linear. The slope and intercept are 1.011 (95% confidence interval: 0.956, 1.067) and -0.41 g/m3

(95% CI: -1.109, 0.271). Since the confidence interval of the slope contains 1 and that of intercept 

contains 0, the difference between the sites is not statistically significant. 

The AMTAC guideline suggests performing a paired T-test to compare the values from the sites. This 

test essentially asks whether the average difference is significantly different from zero. For these 

data, the p-value of the test is 0.08 and 95% confidence interval for the difference in 24-hr averages 

between the sites is -0.04 to 0.62 g/m3

. This also suggests that there is not a statistically significant 

difference between the locations. 

Finally, the 90% upper bound coefficient of variation (C.V.) between the two sites was calculated 

according to the formulae in section 4.4 of Appendix A to 40 CFR 58. Daily averages less than 

Daily 8-hr Max Ozone by Month 

 1990-2014

ozone, ppb

Jan

FebMar

Apr

May

Jun

Jul

AugSep

Oct

NovDec

0 20 40 60 80 100

Median

Maximum

2014

2013

2012

2011

2010

2009

2008

2007

2006

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2004

2003

2002

2001

2000

1999

1998

1997

1996

1995

1994

1993

1992

1991

1990
53 

3 g/m3

 were excluded from the calculation. By this method, the C.V. is calculated to be 11%. 

SLOCAPCD considers this result to be evidence for comparability, given that the Appendix A goal for 

collocated monitors is 10% or less, and these monitors were not collocated, had different probe 

heights, and employed slightly different methods (VSCC vs SCC). 

Figure E-3: Comparison of 24-hr PM2.5 averages. 

0 10 20 30

0 5 10 15 20 25 30 35

Daily PM2.5 

December 18, 2014 to February 23, 2015

Lewis Ave (original site); ug/m3

Traffic Way (new site); ug/m3

24-hr average

R2 : 0.95

m : 1.01

b : -0.42

C.V.: 11 %

1:1 line
54 

Ozone Analysis 

The analysis of ozone was conducted using daily maximum 8-hr averages. Only hours in which both 

sites had valid data were allowed to be included in 8-hr averages. For an 8-hr average to be valid, it 

had to comprise six or more valid hourly values. The window of the daily maximum 8-hr average at 

one site was not required to correspond with the window at the other site. 

A scatterplot of daily 8-hr maxima is shown in Figure E-4 along with the least squares fit. The R2

 of 

the least square fit is 0.99, indicating an excellent linear fit. The slope and intercept are 1.004 (95% 

CI: 0.979, 1.067) and -0.53 ppb (95% CI: -1.233, 0.170). Since the confidence interval of the slope 

contains 1 and that of intercept contains 0, the difference between the sites is not statistically 

significant. 

Applying the T-test suggested by AMTAC results in a p-value of 1.13 × 10-6 and a 95% confidence 

interval for the difference in daily maxima of 0.27 to 0.59 ppb. This suggests that there is small but 

statistically significant difference between the locations, with the Traffic Way site measuring slightly 

lower values. This difference could easily be due to the slightly different instrument calibrations 

noted above. Applying the C.V. test yields a difference of 2%, which we interpret as evidence for 

comparability. 

Finally, Figure E-5 depicts a typical “strip chart,” comparing the ozone values recorded at each site 

minute by minute. The sites track each other closely, suggesting comparability. 

Conclusion 

PM2.5 was monitored at both locations during the season that historically has had the highest 

concentrations. Various statistical tests were applied to the 24-hr averages from these sites, and 

none indicated a statistically significant difference. The upper bound coefficient of variation between 

the monitors was only slightly higher than the data quality objective for collocated monitors; 

however these monitors were not collocated. In summary, the data, while limited, suggest that there 

is not a significant difference in the PM2.5 levels measured at these sites. 

Ozone was also monitored at these locations, but it was monitored during the time of year that 

historically has been the low season. Statistical tests comparing the daily 8-hr maxima from these 

sites found either no significant difference or only a very small—less than 1 ppb—difference 

between the locations. This small difference is likely due to differences in instrument calibration. In 

summary, these limited data suggest that ozone measurements at these locations are 

representative of the same area. 
55 

Figure E-4: Comparison of Daily Maximum 8-hr Averages. 

0 10 20 30 40 50

0 10 20 30 40 50

Daily Max 8-hr Ozone 

December 18, 2014 to February 23, 2015

Lewis Ave (original site); ppb

Traffic Way (new site); ppb

Daily Max 8-hr

R2: 0.99

m : 1

b : -0.53

C.V.: 2 %

1:1 line
56 

Figure E-5: A typical strip chart, comparing ozone values at the two sites at 1-minute resolution. 

 0 10 20 30 40 50

Date: 2015-01-23

Hour

Ozone (ppb)

0123456789

1011121314151617181920212223

Traffic Way (new site)

Lewis Ave (original site)
57 

Appendix F: Index to Items in Annual Monitoring Plan Checklist 

This appendix is intended to provide a convenient guide for where to find the content specifically 

required by EPA Region 9’s Annual Monitoring Plan Checklist for 2015. The item numbers 

correspond to those on the checklist. 

Item No. Section, page Notes

General Plan Requirements 

1 Submittal letter 

2 Submittal letter; Introduction, p. 4.

3 Non-SLAMS Monitoring..., p. 17.

4 Open, Closed, and Relocated...., p. 8;

Appendix C, pp. 40-41; 

Appendix D. 

5 Appendix D. 

6 Proposed Network Changes..., p. 16.

7 Proposed Network Changes..., p. 16.

8 Proposed Network Changes..., p. 16.

9 Nitrogen Dioxide Monitoring..., p. 13.

10 Air Quality Data, p. 18. 

11 Air Quality Data, p. 18. 

12 N/A 

13 N/A 

14 SLAMS Air Monitoring..., p 7.

General Particulate Monitoring Requirements

15 N/A 

16 N/A 

17 Appendix C 

18 Appendix C 

PM2.5-Specific Monitoring Requirements

19 Statement Regarding Review..., p. 16.

20 N/A 

21 Appendix A, p. 20. 

22 Appendix A, p. 20. 

23 Appendix B, p. 24. 

24 N/A 

25 Appendix C, pp. 25-45. 

26 Particular Monitoring..., pp. 14-15.

27 Particular Monitoring..., pp. 14-15;

Appendix C, pp. 32-33. 

28 Proposed Network Changes..., p. 16.

29 N/A 

30 N/A 

31 Appendix C, pp. 25-45. 

32 N/A 

33 Appendix C, pp. 25-45. 
58 

34 Appendix C, pp. 25-45. 

PM10-Specific Monitoring Requirements

35 Appendix A, p. 21. 

36 N/A 

37 Appendix C. 

38 N/A 

39 Appendix C. 

40 Appendix C. 

Pb-Specific Monitoring Requirements

41 Appendix A, p. 23. 

42 Appendix A, p. 23. 

43 N/A 

44 N/A 

45 N/A 

46 N/A 

47 N/A 

48 N/A 

General Gaseous Monitoring Requirements

49 Appendix C. 

50 Appendix C. 

O3-Specific Monitoring Requirements

51 Appendix A, p. 19. 

52 Table 2, p.7; 

Ozone Monitoring..., pp. 11-12. 

Appendix C. 

53 Appendix C. 

NO2-Specific Monitoring Requirements

54 Proposed Network Changes..., p. 16.

55 Proposed Network Changes..., p. 16.

56 N/A 

57 Appendix A, p. 21. 

58 N/A 

CO-Specific Monitoring Requirements

59 Proposed Network Changes..., p. 16.

SO2-Specific Monitoring Requirements

60 Appendix A, p. 22. 

NCORE-Specific Monitoring Requirements

61 N/A 

Site or Monitor - Specific Requirements

62-85 Appendix C.